/*
* Copyright (C) 2010 Nokia Corporation and/or its subsidiary(-ies)
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Library General Public
* License as published by the Free Software Foundation; either
* version 2 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Library General Public License for more details.
*
* You should have received a copy of the GNU Library General Public License
* along with this library; see the file COPYING.LIB. If not, write to
* the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
* Boston, MA 02110-1301, USA.
*/
#ifndefMediaQueryMatcher_h
#defineMediaQueryMatcher_h
#include"ScriptState.h"
#include<wtf/Forward.h>
#include<wtf/RefCounted.h>
#include<wtf/Vector.h>
namespace WebCore {
class Document;
class MediaQueryList;
class MediaQueryListListener;
class MediaQueryEvaluator;
class MediaQuerySet;
// MediaQueryMatcher class is responsible for keeping a vector of pairs
// MediaQueryList x MediaQueryListListener. It is responsible for evaluating the queries
// whenever it is needed and to call the listeners if the corresponding query has changed.
// The listeners must be called in the very same order in which they have been added.
class MediaQueryMatcher : public RefCounted<MediaQueryMatcher> {
public:
static PassRefPtr<MediaQueryMatcher> create(Document* document) { return adoptRef(new MediaQueryMatcher(document)); }
~MediaQueryMatcher();
void documentDestroyed();
void addListener(PassRefPtr<MediaQueryListListener>, PassRefPtr<MediaQueryList>);
void removeListener(MediaQueryListListener*, MediaQueryList*);
PassRefPtr<MediaQueryList> matchMedia(const String&);
unsigned evaluationRound() const { return m_evaluationRound; }
void styleResolverChanged();
bool evaluate(const MediaQuerySet*);
private:
class Listener {
public:
Listener(PassRefPtr<MediaQueryListListener>, PassRefPtr<MediaQueryList>);
~Listener();
void evaluate(ScriptState*, MediaQueryEvaluator*);
MediaQueryListListener* listener() { return m_listener.get(); }
MediaQueryList* query() { return m_query.get(); }
private:
RefPtr<MediaQueryListListener> m_listener;
RefPtr<MediaQueryList> m_query;
};
MediaQueryMatcher(Document*);
PassOwnPtr<MediaQueryEvaluator> prepareEvaluator() const;
String mediaType() const;
Document* m_document;
Vector<OwnPtr<Listener> > m_listeners;
// This value is incremented at style selector changes.
// It is used to avoid evaluating queries more then once and to make sure
// that a media query result change is notified exactly once.
unsigned m_evaluationRound;
};
}
#endif // MediaQueryMatcher_h